[QuadList] Plasticizer

[Trevor Brown]

Interesting does not sound like our old friend white powder which was
limited to 3m's 420 (brown box)
and Memorex Chroma 90  Buff boxes, but the problem was long gone by the time
1" tapes came on the scene



Walter 399 was that the pale green spool , reliable or it was 38 years back
just not got the signal to noise of a modern tape
I think V78 was another one in the same bracket 

 

Trevor
UK Member

 

 

From: quadlist-bounces at quadvideotapegroup.com
[mailto:quadlist-bounces at quadvideotapegroup.com] On Behalf Of Steve Greene
Sent: 17 March 2010 16:47
To: quadlist at quadvideotapegroup.com
Subject: Re: [QuadList] Plasticizer

 

Walter,

I worked with a sizable collection of two-inch that straddled the
non-backcoated (3M's 849 and 399) and backcoated (400) tape stocks.  The
white crystalline deposits were common on the backcoated stocks and
non-existent on the non-backcoated stuff.  I suspect it was part of a
program to create stocks that were more supple and less prone to flaking off
the base.

 

Unless you've heard from a materials chemist, I'm leary of unilaterally
declaring it "plasticizer".  I tend to think of it more generically as a
binder hydrolysis by-product.  This fits with the similar experience on the
audio side of the appearance of new back-coated tape stocks being linked to
sticky-shed.

 

Steve Greene
Audiovisual Archivist
Nixon Presidential Library and Museum
(301) 837-1772

>>> walterforsberg at gmail.com 3/17/2010 11:15:02 AM >>>

Hello Quad Groupers-

 

I'm looking for info / documentation / personal experiences any of you may
have had with white plasticizer, offering itself up from the winds/packs of
2" and 1" videotape. 

 

Specifically, are there any trends or commonly believed reasons for this
stuff appearing? (Eg. specific stocks, a particular environmental storage
condition, or manufacturer's container / reel materials.)

 

I'd also be happy to receive a quoted forward of past discussions on this
topic, as I'm a relative newbie to the list. 

 

Happiest shamrocks & thanks in advance,

 

Walter Forsberg

NYU-MIAP

 

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